Generalization and Extinction of Concept-BasedPain-Related Fear.J Pain. 2019 Mar; 20(3):325-338.JP
In chronic pain, pain-related fear seems to overgeneralize to safe stimuli, thus contributing to excessive fear and avoidance behavior. Evidence shows that pain-related fear can be acquired and generalized based on conceptual knowledge. Using a fear conditioning paradigm, we investigated whether this concept-based pain-related fear could also be extinguished. During acquisition, exemplars of 1 action category (conditioned stimuli [CSs]; eg, opening boxes) were followed by pain (CS+), whereas exemplars of another action category were not (CS-; eg, closing boxes). Participants reported more pain-related fear and expectancy toward exemplars of the CS+ category compared with those of the CS- category. During generalization, fear and expectancy spread to novel exemplars (generalization stimuli [GSs]) of the CS+ category (GS+), but not to those of the CS- category (GS-). During extinction, exemplars of both categories were presented in the absence of pain. At the end of extinction, participants no longer reported elevated fear or expectancy toward CS+ exemplars compared to CS- exemplars. These findings were not replicated in either the eye-blink startle or skin conductance measures. This is the first study to demonstrate extinction of concept-based pain-related fear, thus providing evidence for the potential of extinction-based techniques in the treatment of conceptual pain-related fear. PERSPECTIVE: This study demonstrates the acquisition, generalization, and extinction of concept-based pain-related fear in healthy participants. These are the first results to show that concept-based pain-related fear can be extinguished, suggesting that conceptual relationships between fear-inducing stimuli may also be important to consider in clinical practice.